According to the report by the United Nations in 2015, the global population of older persons aged 60 years or over is predicted to grow to 1.4 billion by 2030. A rapidly aging population poses a challenging problem for human beings, i.e. supply shortage of working-age people. To solve this problem, increasing research efforts are poured into the field of robotics, especially in service robotics. Service robots are believed to be a solid solution to the challenging problem of an aging population. The Strategic Research Agenda (SRA) for Robotics in Europe, a development guideline for European robotics from 2014 to 2020, classifies robots’ functions into eight basic categories, i.e., assembly, surface process, interaction, exploration, transporting, inspection, grasping and manipulation. From SRA, we can find that grasping is an important basic function for robots. Combining grasping with other basic functions, robots can perform many service tasks to free humans from tedious housework, for example, cleaning rooms, cooking and washing dishes.